In-line centrifugal pump with fabricated volutes



Oct. 7, 1952 RUETJEN 2,612,843

IN-LINE CENTRIF'UGAL PUMP WITH FABRICATED VOLUTES Filed March 16, 1946 3 Sheets-Sheet l [12 Van or Oct. 7, 1952 F. A. GRUETJEN 2,612,843

IN-LINE CENTRIFUGAL PUMP WITH FABRICATED VOLUTES 5 Sheets-Sheet 2 Filed March 16, 1946 IN-LINE CENTRIFUGAL PUMP WITH FABRICATED VOLUTES Filed March 16, 1946 Oct. 7, 1952 F. A. GRUETJEN 3 Sheets-Sheet 3 H (((UUHH(MUM((((((((((L((((((((( Patented Oct; 7, 1952 "OFFICE I FABRIcA'rED vo Urns; FredcriclgGrpetjen, Mil-waulree,;,wis.,- assignor to A. G. Smith Corporation, Milwaukee, Wii,

a corporation of New York v I diipli'atitd Maren 16, 1946; semi na than This invention-relates to an in line'eentrifugal pump and has particularreference to a" pump in which the volutes are fabricated in several parts from sheet metal.

The principal object is to provide a pump in which the double volute thereof is of sheet metal fabricated from several parts.

Another object is to provide an in-line centrifugal'pump of less costly construction andof lighter Weight.

These and other objects of the invention will appear hereinafter in connection with the following description. of the drawing illustrating an embodiment of the invention.

In the drawing:

Figure 1 is a longitudinal sectional view of an in-line centrifugal pump constructed in: accordance with the invention;

Fig? 2 is a transverse section taken on line 2-2 of Figure 1 and showing the double volute construction;

Fig. 3 is ariend view of the housingviewed from the right, with the rear nozzle removed;

and

Fig. 4' is an elevational view of the pump with parts broken away to more clearly show the volutes. t

The in-line centrifugal pump illustrated inthe drawings comprisesin general, a double walled fabricated metal housing 1 containing the elec tric motor 2 andpump impeller 3, and a fabricated suction nozzle 4 at the forward end of the housing and acast discharge nozzle 5 at the rear end of the housing. The impeller 3 is mounted on the forward end of the motor shaft 6 of motor 2. g

The housing I is fabricated fromapair of concentrically disposed metal tubes comprising an inner tube! and an outer tube 8 spaced apart a substantial distance to provide an annular passage 9 therebetwe'en' throughout the extent of the housing. I 7 g The annular ring it! is welded to the" ear end of the outer tube 8 and a plurality of flanges H extend inwardly therefrom and are welded to the rear end of the inner tube 1. The discharge nozzle 5 is bolted to' the ring I0 The annular ring 12' is" welded to the fdrward end of outer tube 8. The suction nozzle! is preferably fabricated by welding the end flanges l3 thereof to the central tubular portion. M and the inner end flange [3 is bolted to ring I2.

The tubes 1 and 8 of housing I besides being spaced by flanges H of ring In at the rear end thereof are also held in spaced relation by thetion of inner tube l.

inserts [5 which are welded to the tubes within annular: passage 9 adjacent the forward end of the housingand by" the ring 12 which lies inside outerfitube Band is welded thereto and to inner tube 1. I

The motor 2 is disposed within motor chamber It of housing I and is keyed to the inner tube 1 of the housin'g' by key ll.

The-motor chamber 16 is closed at the forward end by ringw l8 which is welded to the inside of the innerxtube 1 at aline slightly removed from the forward end thereof. The chamber It is closed at the rear end by radial flange 19 disposed within the end er the tube and cap 20 of the discharge" nozzle 5.

The shaft 6 of inotor 2 is supported for free rotation within the forward radial bearing 2| and the rear radialbearing 22. Bearing 2| is held by thering i8 and bearing 22 is secured within flange l9.

- The impeller 3 which is-mounted on the forwarderid of motor shaft 6 is disposed within a'p'iirnp'chamb'er formed between the ring 23 disposed adjacent ring [8, suction nozzle 4', ring 12, flange I 3 of no'zale- 4', and the forward end por- The motor chamber I6 is sealed off from the pump chamber by the fire seal 24 which com-. I

prises a sleeve welded to the inside of ring 18 and concentrically surrounding a flange on shaft 6. The seal 24 prevents sparks or fire in motor chamber 16 from reaching the fluidin the pump chamber;

' Passage of fluid from the pump chamber to the motor chaniberis prevented by positive seal 25 disposed around shaft [5 to the inside of radial passage-26 formed between rings l8 and 23 and leading through inserts 15,; Passage 26 is provided to drain off any fluid such as oil or gasoline that may flow thereto from the pump chamher.- Any' suitable drain pipe; not shown, may be threaded into passage 26 to carry off fluid therefrom. An oil passage 21 extends through ring 18 and inserts I5 to the inside of seal 25' to lubricate bearing 2|. I

The cylindrical wear ring-s 2B are located at the forward side of impeller 3 and cylindrical wear rings- 29 are disposed at the rear side of the impeller. The annular passag-etii is provided at the forward side of the impeller for circulationof a small portion of pumped fluid through the wear rings 28 to nozzle 4 for better hydraulic balance of the impeller. The seal 3| is assembled around shaft 6 and is biased away from impeller 3 by spring 32. Seal 3| operates The double volute 33 comprises four separate volute shaped and matching parts'34 fabricatedlfi from stainless steel and welded together at the circumferential weld joints 35, The welds 36 10111 I the forward side of volute =33 to the ring-l 2 55;. .7 described having an impeller mounted on one and also to the inner tube where the volute curves over tube 1 and is supported thereby. The rear flange of double volute 33 is welded to the inner tube 1 by the welds 31.

The double volute 33 is divided into the upper passage 38 and the lowerpassage 39. Fluid :discharged by impellera3 entersj bothpassagesr-38 and 39 andthenflows intozannularpassage 9 between tubes 1 and; 8. .from whence it flows to discharge nozzle 5 which discharges the fluid from the pump; The-double volute 33 provides a stainless steel conduitjfor the pumped fluid from the impeller discharge to; the annular passage 9 between tubes 2'! and-8 andturns'the fluid from a radial to an axialldirectionz-without any excessive turbulence that would restrict the'flow.

A conduit box 40 maybe provided on the outside of the housing adjacent. the rear-end thereof. Leads, not shown, extend from .=box:.40'through the plug 4| to the stator. or motori2.=Pl.ug 41 is disposed within passage. 9 and is :Welded' to tubes 1 and 8 and ring .lfl. 2a.

After the motor 2 and impeller, 4 with their respective seals and bearings; are ,assembled with tube 1, the separate parts 34 of ,doublevolute? 33, after fabrication, are welded to the inner tube 1 by welds 3! and 36 and'are joined; together-in the same welding operation by the circumferential welds 35.

The ring I2 .is next assembled at the forward end of the pump and the .volute 3,3 is.--joined thereto by weld 36 which is continued from-the joint between tube 1 and the volute 33 previously made. Ring 12. is later welded to the forward end of outer tube 8 when the latteris finally assembled into place. l

The fabricated pump of the invention is light in weight and strong, and fabrication of the volutes from sheet metal overcomes a difficult castingproblem and lightens-the weight ,of the pump at the impeller end. 4

A single volute may be pre-fabricate'd-of several volute shaped parts and welded together and into a pump in the same manner as the double volute described heretofore. l Various embodiments of the invention may be employed within the scope of theaccompanying claims. 1 1

I claim: 1. In an in-line centrifugal pump of described having an impeller mounted on'one end of a shaft driven by an electric motor. a housing for said impeller and motor comprising a pair of tubular members provided from standard pipe sections and concentrically disposed to form a passage therebetween circumferentially the A class 4 surrounding said motor and providing an outlet for fluid discharged by said impeller, an annular ring welded to the outer tubular member at the forward end of said pump, a weld fabricated suction nozzle secured to said ring and providing an inlet for fluid drawn into the pump by said "impeller, and a weld fabricated double volute welded to said inner tubular member on one side and to said inner tubular member and annular ring on the other side and providing curved passages turning fluid discharged by the impeller gi-irqm'j'a radialto'a longitudinal direction and discharging the same into the passage between the tubularpipe-sections.

'2. Ir-"l en iii-line centrifugal pump of the class end ofa shaft driven by an electric motor, a housing for said' impeller and motor comprising a pair oftubular members provided from standard pipe sections and concentrically disposed to form a passage therebetween circumferentially surrounding said motorfiand providing an outlet for fluid discharged bysaid impeller, an annular ring welded to the outer tubular member at the forward end of said pump, a'weld fabricated suction nozzleisecured to :said ring and providing an inlet for fluiddrawn into the pump by said impeller, a weld fabricated channel volute of U- shapedcross-section, a weld joining said volute to the outer surface of the inner tubular member on oneside-and to the inner tubular member and annular ringon the other side and bridging over an opening disposed'betw'een said inner and outer tubular members and providing curved passages to turn fluid discharged by the impellerfrom a radial to'ia. lon l direction to discharge the same into the passage between the tubular pipe sections.

3. In an in-line centrifugal pump having an impeller mounted'on one end of a shaft driven by an electric motor, a housing for said impeller andm'otor'oomprisinga pair of tubular members concentrically secured together with the outer member extending over said impeller and with a passage between said members providing an outlet'for fluid discharge by said impeller, a suction nozzle secured to said housing at one end an' d providing an inlet for fluid drawn into the pump by said impeller, at least one stamped "metal-volute of substantially U-shaped crosssection disposed circumferentially of said im peller within the end of said outer tubular member to discharge fluid from said impeller into said dischargeoutlet passage of the housing, weld means-securing said volute to the end of said inner tubular member, and a ring secured to said volute. and said outer tubular member to close the end of said housing adjacent the impeller.

- FREDERICK A. GRUETJEN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS v2,410,973 Hoover Nov. 12, 1946 

